The invention has as its object a sewing machine, comprising elements for lateral control and positioning of the needle holder bar and for the adjustment of the amplitude and the direction of the movement of the material to be sewn.
A sewing machine is known such as in Swiss Pat. No. 277,952 in which the lateral movements of the needle holder bar and the advance of the feed are controlled by two cams, fastened in a removable way on a drive shaft, in continuous movement, that can be replaced by other interchangeable cams.
By the present invention, an improved arrangement is presented wherein separate, multi-faced cams each controlled by an individual servomotor are located in the machine upper and lower frames and are regulated by suitable control means such as one or more microprocessors to respectively manipulate the lateral needle bar movement and feed dog movement. Additionally, the upper frame cam serves to immobilize the needle bar. In this manner, the two permanently installed cams may be operated in a plurality of coordinated modes to achieve numerous stitching patterns without the necessity of exchanging cam elements as in many prior known machines.